ST. LOUIS (AP) - The last time the Cubs went to the postseason three straight years was in 1906-08. The World Series champions won the National Central for the second straight year with a 5-1 victory over the St. Louis Cardinals on Wednesday night.

Under .500 and trailing Milwaukee in the division race at the All-Star break, the Cubs turned things around with a stellar second half.

"It was tough," starter John Lackey said. "It's always a challenge and we got a lot of people's best shots. We played well and we're back in the playoffs and we'll see what happens."

The Cubs are the first defending World Series champion to win their division the next season since the 2009 Philadelphia Phillies and the first defending champion to reach the playoffs the next season since the Cardinals won the wild card in 2012.

"It's fun to be a team that people want to beat," Cubs infielder Kris Bryant said. "We embrace that and we're going to go with that for as long as we can. It feels good right now knowing they (the Cardinals) always beat up on us before and now we're able to kind of get of a taste of that, too."

The Cubs became the second visiting team to celebrate a title at Busch Stadium III. The 2009 Los Angeles Dodgers won the NLDS at St. Louis.

"It's a blessing to be in a situation to win a World Series on a team and win a division in a tough division the very next year," Cubs outfielder Jason Heyward said. "That's not my plan. That's someone else's plan there. It just happened to be here. Fans, rivalry, whatever, it is what it is, but I know we had a lot of fun competing."

Lackey (12-11) retired the final 10 batters he faced. The former Cardinal and three-time World Series winner struck out three and gave up two hits and two walks.

"I've got to keep telling these kids (young Cubs players) 'Don't take anyone of these for granted. You never know if it's your last one,'" Lackey said. "If you start thinking this is something easy, it's time for you to go home."

Six Cubs relievers combined for three scoreless innings.

Cardinals starter Michael Wacha needed just 60 pitches to cruise through the first six innings, striking out eight, before running into trouble in the seventh. Anthony Rizzo and Bryant started the inning with singles and Russell drove a 2-1 pitch over the left field wall to give the Cubs a 3-1 lead.

Wacha (12-9) was chased after allowing the first six Cubs to reach base in the seventh. Heyward and Tommy La Stella had RBI doubles as the Cubs sent 10 batters to the plate against three St. Louis pitchers.

Paul DeJong's single scored Jedd Gyorko to give the Cardinals a 1-0 lead in the second.

Former Cub Dexter Fowler came to the plate with the bases loaded as the tying run in the eighth, but Carl Edwards Jr. got him to fly weakly to right field, ending the Cardinals' threat.

The loss drops the Cardinals elimination number to one.

Cardinals manager Mike Matheny didn't watch the Cubs' celebration.

"Usually when I watch we don't have any more games to play," Matheny said. "We're getting ready for tomorrow. When I watch in the playoffs it's because our season was over. Our season is not over."

The Cubs will draw Washington in the NLDS, but Lackey isn't focused on the Nationals yet.

"I think we're going to have a good time tonight," Lackey said. "I don't really care about the Nationals."

BAD BLOOD

Rizzo was hit by a 99 mph fastball on the first pitch he saw from Wacha with two outs and nobody on in the first. Rizzo was visibly upset after getting hit, throwing his bat over-handed towards the Cubs' dugout.

Earlier in the day, Cardinals OF Tommy Pham told media that he believed he was hit by a pitch on purpose by the Cubs in Tuesday night's game.

Both batters were hit in the ribs.

TRAINING ROOM

Cubs: OF Albert Almora Jr. (bruised right shoulder) is day-to-day.

Cardinals: C Yadier Molina will undergo further testing under the league's concussion protocol.

UP NEXT

Cubs: RHP Kyle Hendricks (7-5, 3.14 ERA) has made eight consecutive quality starts. He is 2-2 with a 3.62 ERA in his career against St. Louis, including taking a no-hitter into the ninth inning in his last start at Busch Stadium on Sept. 12, 2016.

Cardinals: RHP Lance Lynn (11-8, 3.47 ERA) could possibly be making his final start as a Cardinal after six seasons with the club. Lynn, an unrestricted free agent, is 6-6 with a 4.18 ERA in 18 career appearances against Chicago.